I think it is probably a little bit of both. An MMA fighter has a lot more things to think about and be watching for in a fight than a boxer does. The stances in MMA also might not be as good for slipping punches as a typical boxing stance because they have to be prepared for leg kicks, takedowns etc.

I think your second point is valid also. I haven't seen terribly many MMA fighters who have really high level boxing, but their training has to cover a lot more bases than a boxers training.

That being said, anderson Silva is pretty sweet when it comes to dodging punches.

That and the risk of getting hit is much more with the tiny little gloves versus the 16 oz gloves a boxer will wear. It doesn't take much to knock someone out with the little gloves they have. There is also no padding on the shins and knees. Deflecting is a more conservative strategy. I haven't seen many MMA fighters trade blows with each other like boxers do for obvious reasons. Any punch or kick can be an instant KO or takedown if they are not careful and they usually just can't streamroll in like a Tyson or Joe Frazier because of the clinch game and takedowns. Isn't the hit rate higher for MMA bouts vs. Boxing bouts?

The only two guys I've seen that can avoid punches like that are Anderson Silva and Machica. Perhaps if more pro boxers turned MMA and got really good at grappling as well so they wouldn't be afraid of being taken down we might see more about it. Anderson Silva is pretty much the closest MMA has right now.

That and the risk of getting hit is much more with the tiny little gloves versus the 16 oz gloves a boxer will wear.

It is a misconception that pro boxing matches are held with 16oz gloves. Pro bouts up to Middleweight (160lbs) are held with 8oz gloves, anything above 160lbs. are held with 10oz gloves. No sanctioned fights are held with anything higher then 10oz (at least to my knowledge).

It is a misconception that pro boxing matches are held with 16oz gloves. Pro bouts up to Middleweight (160lbs) are held with 8oz gloves, anything above 160lbs. are held with 10oz gloves. No sanctioned fights are held with anything higher then 10oz (at least to my knowledge).

16oz may be used for some amateur bouts, but when i did boxing in college we always used 12s or 14s.

I think the distance explanation is pretty dead on, with a further distance from your opponent, a lot of punches are already out of range (no need for slipping), and with the exception of silva/machida, by the time you get in slipping range, most guys are looking for the clinch or takedown. If they're not, they're probably just looking to swing anyway (no need for slipping).